Continuous Fiber Optic Functionality Monitoring and Self-Diagnostic Reporting System

ABSTRACT

Disclosed herein is a system, apparatus and method directed to detecting damage to an optical fiber of a medical device. The optical fiber includes one or more core fibers each including a plurality of sensors configured to (i) reflect a light signal based on received incident light, and (ii) alter the reflected light signal for use in determining a physical state of the multi-core optical fiber. The system also includes a console having non-transitory computer-readable medium storing logic that, when executed, causes operations of providing a broadband incident light signal to the multi-core optical fiber, receiving reflected light signals, receiving reflected light signals of different spectral widths of the broadband incident light by one or more of the plurality of sensors, identifying at least one unexpected spectral width or a lack of an expected spectral width, and determining the damage has occurred to the optical fiber based on the identification.

PRIORITY

This application claims the benefit of priority to U.S. ProvisionalApplication No. 63/050,641, filed Jul. 10, 2020, which is incorporatedby reference in its entirety into this application.

BACKGROUND

In the past, certain intravascular guidance of medical devices, such asguidewires and catheters for example, have used fluoroscopic methods fortracking tips of the medical devices and determining whether distal tipsare appropriately localized in their target anatomical structures.However, such fluoroscopic methods expose patients and their attendingclinicians to harmful X-ray radiation. Moreover, in some cases, thepatients are exposed to potentially harmful contrast media needed forthe fluoroscopic methods.

More recently, electromagnetic tracking systems have been used involvingstylets. Generally, electromagnetic tracking systems feature threecomponents: a field generator, a sensor unit and control unit. The fieldgenerator uses several coils to generate a position-varying magneticfield, which is used to establish a coordinate space. Attached to thestylet, such as near a distal end (tip) of the stylet for example, thesensor unit includes small coils in which current is induced via themagnetic field. Based on the electrical properties of each coil, theposition and orientation of the medical device may be determined withinthe coordinate space. The control unit controls the field generator andcaptures data from the sensor unit.

Although electromagnetic tracking systems avoid line-of-sight reliancein tracking the tip of a stylet while obviating radiation exposure andpotentially harmful contrast media associated with fluoroscopic methods,electromagnetic tracking systems are prone to interference. Morespecifically, since electromagnetic tracking systems depend on themeasurement of magnetic fields produced by the field generator, thesesystems are subject to electromagnetic field interference, which may becaused by the presence of many different types of consumer electronicssuch as cellular telephones. Additionally, electromagnetic trackingsystems are subject to signal drop out, depend on an external sensor,and are defined to a limited depth range.

Disclosed herein is a fiber optic shape sensing system and methodsperformed thereby where the system is configured to provide confirmationof tip placement or tracking information using optical fiber technology.Further, the system is configured to detect damage to one or more corefibers and, optionally, a location of the damage along the corefiber(s). Some embodiments combine the fiber optic shape sensingfunctionality with one or more of intravascular electrocardiogram (ECG)monitoring, impedance/conductance sensing and blood flow directionaldetection.

SUMMARY

Briefly summarized, embodiments disclosed herein are directed tosystems, apparatus and methods for obtaining three-dimensional (3D)information (reflected light) corresponding to a trajectory and/or shapeof a medical instrument, such as a catheter, a guidewire, or a stylet,via a fiber optic core during advancement through a vasculature of apatient, monitoring a health of the fiber optic core, and determiningwhen a kink or damage has occurred to the fiber optic core.

More particularly, in some embodiments, the medical instrument includescore optical fiber core configured with an array of sensors (reflectivegratings), which are spatially distributed over a prescribed length ofthe core fiber to generally sense external strain on those regions ofthe core fiber occupied by the sensor. The optical fiber core isconfigured to receive broadband light from a console during advancementthrough the vasculature of a patient, where the broadband lightpropagates along at least a partial distance of the optical fiber coretoward the distal end. Given that each sensor positioned along theoptical fiber core is configured to reflect light of a different,specific spectral width, the array of sensors enables distributedmeasurements throughout the prescribed length of the multi-core opticalfiber. These distributed measurements may include wavelength shiftshaving a correlation with strain experienced by the sensor.

The reflected light from the sensors (reflective gratings) within theoptical fiber core is returned from the medical instrument forprocessing by the console. The physical state of the medical instrumentmay be ascertained based on analytics of the wavelength shifts of thereflected light. For example, the strain caused through bending of themedical instrument, and hence angular modification of the optical fibercore, causes different degrees of deformation. The different degrees ofdeformation alter the shape of the sensors (reflective grating)positioned on the optical fiber core, which may cause variations(shifts) in the wavelength of the reflected light from the sensorspositioned on the optical fiber core. The optical fiber core maycomprise a single optical fiber, or a plurality of optical fibers (inwhich case, the optical fiber core is referred to as a “multi-coreoptical fiber”).

As used herein, the term “core fiber,” generally refers to a singleoptical fiber core disposed within a medical device. Thus, discussion ofa core fiber refers to single optical fiber core and discussion of amulti-core optical fiber refers to a plurality of core fibers. Variousembodiments discussed below to detection of the health (and particularlythe damage) that occurs in each of an optical fiber core of medicaldevice including (i) a single core fiber, and (ii) a plurality of corefibers.

Specific embodiments of the disclosure include utilization of a medicalinstrument, such as a stylet, featuring a multi-core optical fiber and aconductive medium that collectively operate for tracking placement witha body of a patient of the stylet or another medical device (such as acatheter) in which the stylet is disposed. In lieu of a stylet, aguidewire may be utilized. For convenience, embodiments are generallydiscussed where the optical fiber core is disposed within a stylet;however, the disclosure is not intended to be so limited as thefunctionality involving detection of the health of an optical fiber coredisclosed herein may be implemented regardless of the medical device inwhich the optical fiber core is disposed.

In some embodiments, the optical fiber core of a stylet is configured toreturn information for use in identifying its physical state (e.g.,shape length, shape, and/or form) of (i) a portion of the stylet (e.g.,tip, segment of stylet, etc.) or a portion of a catheter inclusive of atleast a portion of the stylet (e.g., tip, segment of catheter, etc.) or(ii) the entirety or a substantial portion of the stylet or catheterwithin the body of a patient (hereinafter, described as the “physicalstate of the stylet” or the “physical state of the catheter”). Accordingto one embodiment of the disclosure, the returned information may beobtained from reflected light signals of different spectral widths,where each reflected light signal corresponds to a portion of broadbandincident light propagating along a core of the multi-core optical fiber(hereinafter, “core fiber”) that is reflected back over the core fiberby a particular sensor located on the core fiber. One illustrativeexample of the returned information may pertain to a change in signalcharacteristics of the reflected light signal returned from the sensor,where wavelength shift is correlated to (mechanical) strain on the corefiber.

In some embodiments, the core fiber utilizes a plurality of sensors andeach sensor is configured to reflect a different spectral range of theincident light (e.g., different light frequency range). Based on thetype and degree of strain asserted on each core fiber, the sensorsassociated with that core fiber may alter (shift) the wavelength of thereflected light to convey the type and degree of stain on that corefiber at those locations of the stylet occupied by the sensors. Thesensors are spatially distributed at various locations of the core fiberbetween a proximal end and a distal end of the stylet so that shapesensing of the stylet may be conducted based on analytics of thewavelength shifts. Herein, the shape sensing functionality is pairedwith the ability to simultaneously pass an electrical signal through thesame member (stylet) through conductive medium included as part of thestylet.

More specifically, in some embodiments each core fiber of the multi-coreoptical fiber is configured with an array of sensors, which arespatially distributed over a prescribed length of the core fiber togenerally sense external strain those regions of the core fiber occupiedby the sensor. Given that each sensor positioned along the same corefiber is configured to reflect light of a different, specific spectralwidth, the array of sensors enables distributed measurements throughoutthe prescribed length of the multi-core optical fiber. These distributedmeasurements may include wavelength shifts having a correlation withstrain experienced by the sensor.

According to one embodiment of the disclosure, each sensor may operateas a reflective grating such as a fiber Bragg grating (FBG), namely anintrinsic sensor corresponding to a permanent, periodic refractive indexchange inscribed into the core fiber. Stated differently, the sensoroperates as a light reflective mirror for a specific spectral width(e.g., a specific wavelength or specific range of wavelengths). As aresult, as broadband incident light is supplied by an optical lightsource and propagates through a particular core fiber, upon reaching afirst sensor of the distributed array of sensors for that core fiber,light of a prescribed spectral width associated with the first sensor isreflected back to an optical receiver within a console, including adisplay and the optical light source. The remaining spectrum of theincident light continues propagation through the core fiber toward adistal end of the stylet. The remaining spectrum of the incident lightmay encounter other sensors from the distributed array of sensors, whereeach of these sensors is fabricated to reflect light with differentspecific spectral widths to provide distributed measurements, asdescribed above.

During operation, multiple light reflections (also referred to as“reflected light signals”) are returned to the console from each of theplurality of core fibers of the multi-core optical fiber. Each reflectedlight signal may be uniquely associated with a different spectral width.Information associated with the reflected light signals may be used todetermine a three-dimensional representation of the physical state ofthe stylet within the body of a patient. Herein, the core fibers arespatially separated with the cladding of the multi-mode optical fiberand each core fiber is configured to separately return light ofdifferent spectral widths (e.g., specific light wavelength or a range oflight wavelengths) reflected from the distributed array of sensorsfabricated in each of the core fibers. A comparison of detected shiftsin wavelength of the reflected light returned by a center core fiber(operating as a reference) and the surrounding, periphery core fibersmay be used to determine the physical state of the stylet.

During vasculature insertion and advancement of the catheter, theclinician may rely on the console to visualize a current physical state(e.g., shape) of a catheter guided by the stylet to avoid potential pathdeviations. As the periphery core fibers reside at spatially differentlocations within the cladding of the multi-mode optical fiber, changesin angular orientation (such as bending with respect to the center corefiber, etc.) of the stylet imposes different types (e.g., compression ortension) and degrees of strain on each of the periphery core fibers aswell as the center core fiber. The different types and/or degree ofstrain may cause the sensors of the core fibers to apply differentwavelength shifts, which can be measured to extrapolate the physicalstate of the stylet (catheter).

Embodiments of the disclosure may include a combination of one or moreof the methodologies to determine when an optical fiber within a body ofimplementation (e.g., an introducer wire, a guidewire, a stylet within aneedle, a needle with fiber optic inlayed into the cannula, a styletconfigured for use with a catheter, an optical fiber between a needleand a catheter, and/or an optical fiber integrated into a catheter) hasincurred damage and/or been kinked such that a portion of the opticalfiber is non-functional (i.e., unable to provide accurate, uncorruptedreflected light signals back to a console).

Certain embodiments of the disclosure pertain to the utilization offiber optic shape sensing to track advancement of a body ofimplementation throughout the vasculature of a patient and detectingdamage to one or more core fibers of the optical fiber integrated intothe body of implementation. For example, as noted above, each core fiberincludes a plurality of reflective gratings disposed along its length,wherein each reflective grating receives broadband incident light andreflects light signals having a specific spectral width (e.g., aspecific wavelength or specific range of wavelengths) that may beshifted based on an amount of strain applied to a length of the corefiber corresponding to the reflective grating. Detection of damage to acore fiber is performed through an analysis of the received reflectedlight signals and, specifically, identification of reflective gratingsfrom which a corrupted or degraded reflected light signal was received,a reflected light signal was received having a reduced intensity (e.g.,power transferred per unit area) or a reflected light signal was notreceived.

Further, some embodiments include analysis of the specific spectralwidth of each received reflected light signal to determine a locationalong the core fiber at which damage (or a kink) occurred. Specifically,logic of the console determines from which core fiber each reflectedlight signal was received and further analyzes the specific spectralwidth of each received reflected light signal to identify (i) a mostdistal reflective grating from which a normal, uncorrupted light signalwas received, and a (ii) a most proximal reflective grating from which acorrupted (e.g., degraded) light signal was received. Such anidentification of reflective gratings results in an identification ofthe location of the kink or point of damage.

Further embodiments of the disclosure pertain to the use of fiber opticshape sensing to identify damage to a core fiber and the locationthereof as well as to detect fluctuation of the body of implementation.For example, deviation of the advancement of the body of implementationout of the SVC into the Azygos vein is identified via a reduction influctuations in the body of implementation. Additionally, intravascularECG monitoring may be combined with either or both of the fiber opticshape sensing methodologies referenced above to detect deviation of theadvancement of the body of implementation into the Azygos vein as thedetected P-wave of the intravascular ECG decreases in slightly inamplitude even as the body of implementation is advanced towards thesinoatrial (SA) node. Additionally, or in the alternative,impedance/conductance sensing may be combined with either or both of thefiber optic shape sensing methodologies and, optionally, the ECGintravascular ECG monitoring to detect deviation of the advancement ofthe body of implementation into the Azygos vein. For instance, as thebody of implementation deviates into the Azygos vein the smallerdiameter vessel is characterized by a varied impedance/conductance.

In yet other embodiments, the direction of the blood flow may beutilized in combination with any of the fiber optic shape sensingmethodologies, intravascular ECG monitoring and/or impedance/conductancesensing referenced above. For instance, as the body of implementationdeviates into the Azygos vein, the flow of blood will change fromin-line with the advancement of the body of implementation to againstthe advancement of the body of implementation, which may be detectedusing pulse oximetry and/or blood flow Doppler.

Some embodiments include a medical device system for detecting damage toa optical fiber technology of a medical device, where the systemcomprises the medical device including an optical fiber having one ormore of core fibers, each of the one or more core fibers including aplurality of sensors distributed along a longitudinal length of acorresponding core fiber and each sensor of the plurality of sensorsbeing configured to (i) reflect a light signal of a different spectralwidth based on received incident light, and (ii) change a characteristicof the reflected light signal for use in determining a physical state ofthe optical fiber. The system may also include a console including oneor more processors and a non-transitory computer-readable medium havingstored thereon logic, when executed by the one or more processors,causes operations including providing a broadband incident light signalto the optical fiber, receiving reflected light signals of differentspectral widths of the broadband incident light by one or more of theplurality of sensors, processing the reflected light signals associatedwith the one or more of core fibers to identify at least one unexpectedspectral width or a lack of an expected spectral width, and determiningthe damage has occurred to one or more of the core fibers based onidentification of the at least one unexpected spectral width or the lackof an expected spectral width.

In some embodiments, an unexpected spectral width is a spectral widthnot configured for use by any of the plurality of sensors of a corefiber. In some embodiments, the optical fiber is a single-core opticalfiber. In other embodiments, the optical fiber is a multi-core opticalfiber including a plurality of core fibers. In some embodiments, thedamage affects a first subset of the plurality of core-fibers.

In some embodiments, a second subset of the plurality of core fibers isunaffected by the damage such that multi-core optical fiber maintains atleast partial functionality based on the second subset of the pluralityof core-fibers. In some embodiments, the at least partial functionalityincludes one or more of fluctuation sensing of a distal tip of themedical device, shape sensing of the multi-core optical fiber, oximetrymonitoring, distal tip confirmation, distal tip location detection,detection of entry of the distal tip of the medical device into anAzygos vein, impedance or conductance sensing, intravascular ECGmonitoring or vessel cannulation detection.

In further embodiments, the logic, when executed by the one or moreprocessors, causes further operations including performing at leastpartial functionality of the multi-core optical fiber withoutconsidering information provided by a first core fiber that hasreflected a light signal having a first unexpected wavelength. In someembodiments, the second subset of the plurality of core fibers includesredundant core fibers such that a shape sensing functionality of themulti-core optical fiber is maintained. In yet other embodiments, themedical device is one of an introducer wire, a guidewire, a stylet, astylet within a needle, a needle with the optical fiber inlayed into acannula of the needle or a catheter with the optical fiber inlayed intoone or more walls of the catheter.

In some embodiments, the logic, when executed by the one or moreprocessors, causes further operations including determining a first corefiber affected by the damage, and determining a location of the damagealong the first core fiber. In some embodiments, determining the firstcore fiber is based on a unique identifier assigned to the first corefiber and association of unique identifier with each light signalreflected by the first core fiber. In some embodiments, determining thelocation of the damage includes identifying (i) a most distal sensor ofthe first core fiber from which a first light signal having an expectedspectral width was received, and a (ii) a most proximal sensor fromwhich a second light signal having a first unexpected spectral width wasreceived, second light signal having a reduction in intensity wasreceived or a corresponding expected spectral width was not received. Inyet further embodiments, each of the plurality of sensors is areflective grating, where each reflective grating alters its reflectedlight signal by applying a wavelength shift dependent on a strainexperienced by the reflective grating.

Some embodiments include a method for placing a medical device into abody of a patient, the method comprising certain operations includingproviding a broadband incident light signal to an optical fiber includedwithin the medical device, wherein the optical fiber includes a one ormore of core fibers, each of the one or more of core fibers including aplurality of reflective gratings distributed along a longitudinal lengthof a corresponding core fiber and each of the plurality of reflectivegratings being configured to (i) reflect a light signal of a differentspectral width based on received incident light, and (ii) change acharacteristic of the reflected light signal for use in determining aphysical state of the optical fiber and receiving reflected lightsignals of different spectral widths of the broadband incident light byone or more of the plurality of sensors. The operations further includeprocessing the reflected light signals associated with the one or moreof core fibers to identify at least one unexpected spectral width or alack of an expected spectral width, and determining the damage hasoccurred to one or more of the core fibers based on identification ofthe at least one unexpected spectral width or the lack of an expectedspectral width.

In some embodiments, an unexpected spectral width is a spectral widthnot configured for use by any of the plurality of sensors of a corefiber. In some embodiments, the optical fiber is a single-core opticalfiber. In other embodiments, the optical fiber is a multi-core opticalfiber including a plurality of core fibers. In some embodiments, thedamage affects a first subset of the plurality of core-fibers.

In some embodiments, a second subset of the plurality of core fibers isunaffected by the damage such that multi-core optical fiber maintains atleast partial functionality based on the second subset of the pluralityof core-fibers. In some embodiments, the at least partial functionalityincludes one or more of fluctuation sensing of a distal tip of themedical device, shape sensing of the multi-core optical fiber, oximetrymonitoring, distal tip confirmation, distal tip location detection,detection of entry of the distal tip of the medical device into anAzygos vein, impedance or conductance sensing, intravascular ECGmonitoring or vessel cannulation detection.

In further embodiments, the logic, when executed by the one or moreprocessors, causes further operations including performing at leastpartial functionality of the multi-core optical fiber withoutconsidering information provided by a first core fiber that hasreflected a light signal having a first unexpected wavelength. In someembodiments, the second subset of the plurality of core fibers includesredundant core fibers such that a shape sensing functionality of themulti-core optical fiber is maintained. In yet other embodiments, themedical device is one of an introducer wire, a guidewire, a stylet, astylet within a needle, a needle with the optical fiber inlayed into acannula of the needle or a catheter with the optical fiber inlayed intoone or more walls of the catheter.

In some embodiments, the logic, when executed by the one or moreprocessors, causes further operations including determining a first corefiber affected by the damage, and determining a location of the damagealong the first core fiber. In some embodiments, determining the firstcore fiber is based on a unique identifier assigned to the first corefiber and association of unique identifier with each light signalreflected by the first core fiber. In some embodiments, determining thelocation of the damage includes identifying (i) a most distal sensor ofthe first core fiber from which a first light signal having an expectedwavelength was received, and a (ii) a most proximal sensor from which asecond light signal having a first unexpected spectral width wasreceived, second light signal having a reduction in intensity wasreceived or a corresponding expected spectral width was not received. Inyet further embodiments, each of the plurality of sensors is areflective grating, where each reflective grating alters its reflectedlight signal by applying a wavelength shift dependent on a strainexperienced by the reflective grating.

Some embodiments disclose a non-transitory computer-readable mediumhaving stored thereon logic that, when executed by the one or moreprocessors, causes operations including providing a broadband incidentlight signal to an optical fiber included within the medical device,wherein the optical fiber includes a one or more of core fibers, each ofthe one or more of core fibers including a plurality of reflectivegratings distributed along a longitudinal length of a corresponding corefiber and each of the plurality of reflective gratings being configuredto (i) reflect a light signal of a different spectral width based onreceived incident light, and (ii) change a characteristic of thereflected light signal for use in determining a physical state of theoptical fiber and receiving reflected light signals of differentspectral widths of the broadband incident light by one or more of theplurality of sensors. The operations further include processing thereflected light signals associated with the one or more of core fibersto identify at least one unexpected spectral width or a lack of anexpected spectral width, and determining the damage has occurred to oneor more of the core fibers based on identification of the at least oneunexpected spectral width or the lack of an expected spectral width.

In some embodiments, an unexpected spectral width is a spectral widthnot configured for use by any of the plurality of sensors of a corefiber. In some embodiments, the optical fiber is a single-core opticalfiber. In other embodiments, the optical fiber is a multi-core opticalfiber including a plurality of core fibers. In some embodiments, thedamage affects a first subset of the plurality of core-fibers.

In some embodiments, a second subset of the plurality of core fibers isunaffected by the damage such that multi-core optical fiber maintains atleast partial functionality based on the second subset of the pluralityof core-fibers. In some embodiments, the at least partial functionalityincludes one or more of fluctuation sensing of a distal tip of themedical device, shape sensing of the multi-core optical fiber, oximetrymonitoring, distal tip confirmation, distal tip location detection,detection of entry of the distal tip of the medical device into anAzygos vein, impedance or conductance sensing, intravascular ECGmonitoring or vessel cannulation detection.

In further embodiments, the logic, when executed by the one or moreprocessors, causes further operations including performing at leastpartial functionality of the multi-core optical fiber withoutconsidering information provided by a first core fiber that hasreflected a light signal having a first unexpected wavelength. In someembodiments, the second subset of the plurality of core fibers includesredundant core fibers such that a shape sensing functionality of themulti-core optical fiber is maintained. In yet other embodiments, themedical device is one of an introducer wire, a guidewire, a stylet, astylet within a needle, a needle with the optical fiber inlayed into acannula of the needle or a catheter with the optical fiber inlayed intoone or more walls of the catheter.

In some embodiments, the logic, when executed by the one or moreprocessors, causes further operations including determining a first corefiber affected by the damage, and determining a location of the damagealong the first core fiber. In some embodiments, determining the firstcore fiber is based on a unique identifier assigned to the first corefiber and association of unique identifier with each light signalreflected by the first core fiber. In some embodiments, determining thelocation of the damage includes identifying (i) a most distal sensor ofthe first core fiber from which a first light signal having an expectedwavelength was received, and a (ii) a most proximal sensor from which asecond light signal having a first unexpected spectral width wasreceived, second light signal having a reduction in intensity wasreceived or a corresponding expected spectral width was not received. Inyet further embodiments, each of the plurality of sensors is areflective grating, where each reflective grating alters its reflectedlight signal by applying a wavelength shift dependent on a strainexperienced by the reflective grating.

These and other features of the concepts provided herein will becomemore apparent to those of skill in the art in view of the accompanyingdrawings and following description, which disclose particularembodiments of such concepts in greater detail.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the disclosure are illustrated by way of example and notby way of limitation in the figures of the accompanying drawings, inwhich like references indicate similar elements and in which:

FIG. 1A is an illustrative embodiment of a medical instrument monitoringsystem including a medical instrument with optic shape sensing and fiberoptic-based oximetry capabilities in accordance with some embodiments;

FIG. 1B is an alternative illustrative embodiment of the medicalinstrument monitoring system 100 in accordance with some embodiments;

FIG. 2 is an exemplary embodiment of a structure of a section of themulti-core optical fiber included within the stylet 120 of FIG. 1A inaccordance with some embodiments;

FIG. 3A is a first exemplary embodiment of the stylet of FIG. 1Asupporting both an optical and electrical signaling in accordance withsome embodiments;

FIG. 3B is a cross sectional view of the stylet of FIG. 3A in accordancewith some embodiments;

FIG. 4A is a second exemplary embodiment of the stylet of FIG. 1B inaccordance with some embodiments;

FIG. 4B is a cross sectional view of the stylet of FIG. 4A in accordancewith some embodiments;

FIG. 5A is an elevation view of a first illustrative embodiment of acatheter including integrated tubing, a diametrically disposed septum,and micro-lumens formed within the tubing and septum in accordance withsome embodiments;

FIG. 5B is a perspective view of the first illustrative embodiment ofthe catheter of FIG. 5A including core fibers installed within themicro-lumens in accordance with some embodiments;

FIGS. 6A-6B are flowcharts of the methods of operations conducted by themedical instrument monitoring system of FIGS. 1A-1B to achieve optic 3Dshape sensing in accordance with some embodiments;

FIG. 7 is an exemplary embodiment of the medical instrument monitoringsystem of FIG. 1A during operation and insertion of the catheter into apatient in accordance with some embodiments;

FIG. 8 is an embodiment of a structure of a section of a single coreoptical fiber included within the stylet 120 of FIG. 1A that is kinkedor damaged in accordance with some embodiments;

FIG. 9A is an embodiment of a structure of a section of a multi-coreoptical fiber included within the stylet 120 of FIG. 1A that is kinkedor partially damaged in accordance with some embodiments;

FIG. 9B is an embodiment of a structure of a section of a multi-coreoptical fiber included within the stylet 120 of FIG. 1A that iscompletely damaged in accordance with some embodiments.

DETAILED DESCRIPTION

Before some particular embodiments are disclosed in greater detail, itshould be understood that the particular embodiments disclosed herein donot limit the scope of the concepts provided herein. It should also beunderstood that a particular embodiment disclosed herein can havefeatures that can be readily separated from the particular embodimentand optionally combined with or substituted for features of any of anumber of other embodiments disclosed herein.

Regarding terms used herein, it should also be understood the terms arefor the purpose of describing some particular embodiments, and the termsdo not limit the scope of the concepts provided herein. Ordinal numbers(e.g., first, second, third, etc.) are generally used to distinguish oridentify different features or steps in a group of features or steps,and do not supply a serial or numerical limitation. For example,“first,” “second,” and “third” features or steps need not necessarilyappear in that order, and the particular embodiments including suchfeatures or steps need not necessarily be limited to the three featuresor steps. Labels such as “left,” “right,” “top,” “bottom,” “front,”“back,” and the like are used for convenience and are not intended toimply, for example, any particular fixed location, orientation, ordirection. Instead, such labels are used to reflect, for example,relative location, orientation, or directions. Singular forms of “a,”“an,” and “the” include plural references unless the context clearlydictates otherwise.

With respect to “proximal,” a “proximal portion” or a “proximal endportion” of, for example, a probe disclosed herein includes a portion ofthe probe intended to be near a clinician when the probe is used on apatient. Likewise, a “proximal length” of, for example, the probeincludes a length of the probe intended to be near the clinician whenthe probe is used on the patient. A “proximal end” of, for example, theprobe includes an end of the probe intended to be near the clinicianwhen the probe is used on the patient. The proximal portion, theproximal end portion, or the proximal length of the probe can includethe proximal end of the probe; however, the proximal portion, theproximal end portion, or the proximal length of the probe need notinclude the proximal end of the probe. That is, unless context suggestsotherwise, the proximal portion, the proximal end portion, or theproximal length of the probe is not a terminal portion or terminallength of the probe.

With respect to “distal,” a “distal portion” or a “distal end portion”of, for example, a probe disclosed herein includes a portion of theprobe intended to be near or in a patient when the probe is used on thepatient. Likewise, a “distal length” of, for example, the probe includesa length of the probe intended to be near or in the patient when theprobe is used on the patient. A “distal end” of, for example, the probeincludes an end of the probe intended to be near or in the patient whenthe probe is used on the patient. The distal portion, the distal endportion, or the distal length of the probe can include the distal end ofthe probe; however, the distal portion, the distal end portion, or thedistal length of the probe need not include the distal end of the probe.That is, unless context suggests otherwise, the distal portion, thedistal end portion, or the distal length of the probe is not a terminalportion or terminal length of the probe.

The term “logic” may be representative of hardware, firmware or softwarethat is configured to perform one or more functions. As hardware, theterm logic may refer to or include circuitry having data processingand/or storage functionality. Examples of such circuitry may include,but are not limited or restricted to a hardware processor (e.g.,microprocessor, one or more processor cores, a digital signal processor,a programmable gate array, a microcontroller, an application specificintegrated circuit “ASIC”, etc.), a semiconductor memory, orcombinatorial elements.

Additionally, or in the alternative, the term logic may refer to orinclude software such as one or more processes, one or more instances,Application Programming Interface(s) (API), subroutine(s), function(s),applet(s), servlet(s), routine(s), source code, object code, sharedlibrary/dynamic link library (dll), or even one or more instructions.This software may be stored in any type of a suitable non-transitorystorage medium, or transitory storage medium (e.g., electrical, optical,acoustical or other form of propagated signals such as carrier waves,infrared signals, or digital signals). Examples of a non-transitorystorage medium may include, but are not limited or restricted to aprogrammable circuit; non-persistent storage such as volatile memory(e.g., any type of random access memory “RAM”); or persistent storagesuch as non-volatile memory (e.g., read-only memory “ROM”, power-backedRAM, flash memory, phase-change memory, etc.), a solid-state drive, harddisk drive, an optical disc drive, or a portable memory device. Asfirmware, the logic may be stored in persistent storage.

Referring to FIG. 1A, an illustrative embodiment of a medical instrumentmonitoring system including a medical instrument with optic shapesensing and fiber optic-based oximetry capabilities is shown inaccordance with some embodiments. As shown, the system 100 generallyincludes a console 110 and a stylet assembly 119 communicatively coupledto the console 110. For this embodiment, the stylet assembly 119includes an elongate probe (e.g., stylet) 120 on its distal end 122 anda console connector 133 on its proximal end 124, where the stylet 120 isconfigured to advance within a patient vasculature either through, or inconjunction with, a catheter 195. The console connector 133 enables thestylet assembly 119 to be operably connected to the console 110 via aninterconnect 145 including one or more optical fibers 147 (hereinafter,“optical fiber(s)”) and a conductive medium terminated by a singleoptical/electric connector 146 (or terminated by dual connectors.Herein, the connector 146 is configured to engage (mate) with theconsole connector 133 to allow for the propagation of light between theconsole 110 and the stylet assembly 119 as well as the propagation ofelectrical signals from the stylet 120 to the console 110.

An exemplary implementation of the console 110 includes a processor 160,a memory 165, a display 170 and optical logic 180, although it isappreciated that the console 110 can take one of a variety of forms andmay include additional components (e.g., power supplies, ports,interfaces, etc.) that are not directed to aspects of the disclosure. Anillustrative example of the console 110 is illustrated in U.S.Publication No. 2019/0237902, the entire contents of which areincorporated by reference herein. The processor 160, with access to thememory 165 (e.g., non-volatile memory or non-transitory,computer-readable medium), is included to control functionality of theconsole 110 during operation. As shown, the display 170 may be a liquidcrystal diode (LCD) display integrated into the console 110 and employedas a user interface to display information to the clinician, especiallyduring a catheter placement procedure (e.g., cardiac catheterization).In another embodiment, the display 170 may be separate from the console110. Although not shown, a user interface is configured to provide usercontrol of the console 110.

For both of these embodiments, the content depicted by the display 170may change according to which mode the stylet 120 is configured tooperate: optical, TLS, ECG, or another modality. In TLS mode, thecontent rendered by the display 170 may constitute a two-dimensional(2D) or three-dimensional (3D) representation of the physical state(e.g., length, shape, form, and/or orientation) of the stylet 120computed from characteristics of reflected light signals 150 returned tothe console 110. The reflected light signals 150 constitute light of aspecific spectral width of broadband incident light 155 reflected backto the console 110. According to one embodiment of the disclosure, thereflected light signals 150 may pertain to various discrete portions(e.g., specific spectral widths) of broadband incident light 155transmitted from and sourced by the optical logic 180, as describedbelow

According to one embodiment of the disclosure, an activation control126, included on the stylet assembly 119, may be used to set the stylet120 into a desired operating mode and selectively alter operability ofthe display 170 by the clinician to assist in medical device placement.For example, based on the modality of the stylet 120, the display 170 ofthe console 110 can be employed for optical modality-based guidanceduring catheter advancement through the vasculature or TLS modality todetermine the physical state (e.g., length, form, shape, orientation,etc.) of the stylet 120. In one embodiment, information from multiplemodes, such as optical, TLS or ECG for example, may be displayedconcurrently (e.g., at least partially overlapping in time).

Referring still to FIG. 1A, the optical logic 180 is configured tosupport operability of the stylet assembly 119 and enable the return ofinformation to the console 110, which may be used to determine thephysical state associated with the stylet 120 along with monitoredelectrical signals such as ECG signaling via an electrical signalinglogic 181 that supports receipt and processing of the receivedelectrical signals from the stylet 120 (e.g., ports, analog-to-digitalconversion logic, etc.). The physical state of the stylet 120 may bebased on changes in characteristics of the reflected light signals 150received at the console 110 from the stylet 120. The characteristics mayinclude shifts in wavelength caused by strain on certain regions of thecore fibers integrated within an optical fiber core 135 positionedwithin or operating as the stylet 120, as shown below. As discussedherein, the optical fiber core 135 may be comprised of core fibers 137₁-137 M (M=1 for a single core, and M≥2 for a multi-core), where thecore fibers 137 ₁-137 M may collectively be referred to as core fiber(s)137. Unless otherwise specified or the instant embodiment requires analternative interpretation, embodiments discussed herein will refer to amulti-core optical fiber 135. From information associated with thereflected light signals 150, the console 110 may determine (throughcomputation or extrapolation of the wavelength shifts) the physicalstate of the stylet 120, and also that of the catheter 195 configured toreceive the stylet 120.

According to one embodiment of the disclosure, as shown in FIG. 1A, theoptical logic 180 may include a light source 182 and an optical receiver184. The light source 182 is configured to transmit the incident light155 (e.g., broadband) for propagation over the optical fiber(s) 147included in the interconnect 145, which are optically connected to themulti-core optical fiber core 135 within the stylet 120. In oneembodiment, the light source 182 is a tunable swept laser, althoughother suitable light sources can also be employed in addition to alaser, including semi-coherent light sources, LED light sources, etc.

The optical receiver 184 is configured to: (i) receive returned opticalsignals, namely reflected light signals 150 received from opticalfiber-based reflective gratings (sensors) fabricated within each corefiber of the multi-core optical fiber 135 deployed within the stylet120, and (ii) translate the reflected light signals 150 into reflectiondata (from repository 192), namely data in the form of electricalsignals representative of the reflected light signals includingwavelength shifts caused by strain. The reflected light signals 150associated with different spectral widths may include reflected lightsignals 151 provided from sensors positioned in the center core fiber(reference) of the multi-core optical fiber 135 and reflected lightsignals 152 provided from sensors positioned in the periphery corefibers of the multi-core optical fiber 135, as described below. Herein,the optical receiver 184 may be implemented as a photodetector, such asa positive-intrinsic-negative “PIN” photodiode, avalanche photodiode, orthe like.

As shown, both the light source 182 and the optical receiver 184 areoperably connected to the processor 160, which governs their operation.Also, the optical receiver 184 is operably coupled to provide thereflection data (from repository 192) to the memory 165 for storage andprocessing by reflection data classification logic 190. The reflectiondata classification logic 190 may be configured to: (i) identify whichcore fibers pertain to which of the received reflection data (fromrepository 192) and (ii) segregate the reflection data stored with arepository 192 provided from reflected light signals 150 pertaining tosimilar regions of the stylet 120 or spectral widths into analysisgroups. The reflection data for each analysis group is made available toshape sensing logic 194 for analytics.

According to one embodiment of the disclosure, the shape sensing logic194 is configured to compare wavelength shifts measured by sensorsdeployed in each periphery core fiber at the same measurement region ofthe stylet 120 (or same spectral width) to the wavelength shift at acenter core fiber of the multi-core optical fiber 135 positioned alongcentral axis and operating as a neutral axis of bending. From theseanalytics, the shape sensing logic 194 may determine the shape the corefibers have taken in 3D space and may further determine the currentphysical state of the catheter 195 in 3D space for rendering on thedisplay 170.

According to one embodiment of the disclosure, the shape sensing logic194 may generate a rendering of the current physical state of the stylet120 (and potentially the catheter 195), based on heuristics or run-timeanalytics. For example, the shape sensing logic 194 may be configured inaccordance with machine-learning techniques to access a data store(library) with pre-stored data (e.g., images, etc.) pertaining todifferent regions of the stylet 120 (or catheter 195) in which reflectedlight from core fibers have previously experienced similar or identicalwavelength shifts. From the pre-stored data, the current physical stateof the stylet 120 (or catheter 195) may be rendered. Alternatively, asanother example, the shape sensing logic 194 may be configured todetermine, during run-time, changes in the physical state of each regionof the multi-core optical fiber 135 based on at least: (i) resultantwavelength shifts experienced by different core fibers within theoptical fiber 135, and (ii) the relationship of these wavelength shiftsgenerated by sensors positioned along different periphery core fibers atthe same cross-sectional region of the multi-core optical fiber 135 tothe wavelength shift generated by a sensor of the center core fiber atthe same cross-sectional region. It is contemplated that other processesand procedures may be performed to utilize the wavelength shifts asmeasured by sensors along each of the core fibers within the multi-coreoptical fiber 135 to render appropriate changes in the physical state ofthe stylet 120 (and/or catheter 195), especially to enable guidance ofthe stylet 120, when positioned at a distal tip of the catheter 195,within the vasculature of the patient and at a desired destinationwithin the body.

The console 110 may further include electrical signaling logic 181,which is positioned to receive one or more electrical signals from thestylet 120. The stylet 120 is configured to support both opticalconnectivity as well as electrical connectivity. The electricalsignaling logic 181 receives the electrical signals (e.g., ECG signals)from the stylet 120 via the conductive medium. The electrical signalsmay be processed by electrical signal logic 196, executed by theprocessor 160, to determine ECG waveforms for display.

Additionally, the console 110 includes a fluctuation logic 198 that isconfigured to analyze at least a subset of the wavelength shiftsmeasured by sensors deployed in each of the core fibers 137. Inparticular, the fluctuation logic 198 is configured to analyzewavelength shifts measured by sensors of core fibers 137, where suchcorresponds to an analysis of the fluctuation of the distal tip of thestylet 120 (or “tip fluctuation analysis”). In some embodiments, thefluctuation logic 198 measures analyzes the wavelength shifts measuredby sensors at a distal end of the core fibers 137. The tip fluctuationanalysis includes at least a correlation of detected movements of thedistal tip of the stylet 120 (or other medical device or instrument)with experiential knowledge comprising previously detected movements(fluctuations), and optionally, other current measurements such as ECGsignals. The experiential knowledge may include previously detectedmovements in various locations within the vasculature (e.g., SVC,Inferior Vena Cava (IVC), right atrium, azygos vein, other blood vesselssuch as arteries and veins) under normal, healthy conditions and in thepresence of defects (e.g., vessel constriction, vasospasm, vesselocclusion, etc.). Thus, the tip fluctuation analysis may result in aconfirmation of tip location and/or detection of a defect affecting ablood vessel.

It should be noted that the fluctuation logic 198 need not perform thesame analyses as the shape sensing logic 194. For instance, the shapesensing logic 194 determines a 3D shape of the stylet 120 by comparingwavelength shifts in outer core fibers of a multi-core optical fiber toa center, reference core fiber. The fluctuation logic 198 may insteadcorrelate the wavelength shifts to previously measured wavelength shiftsand optionally other current measurements without distinguishing betweenwavelength shifts of outer core fibers and a center, reference corefiber as the tip fluctuation analysis need not consider direction orshape within a 3D space.

In some embodiments, e.g., those directed at tip location confirmation,the analysis of the fluctuation logic 198 may utilize electrical signals(e.g., ECG signals) measured by the electrical signaling logic 181. Forexample, the fluctuation logic 198 may compare the movements of asubsection of the stylet 120 (e.g., the distal tip) with electricalsignals indicating impulses of the heart (e.g., the heartbeat). Such acomparison may reveal whether the distal tip is within the SVC or theright atrium based on how closely the movements correspond to a rhythmicheartbeat.

In various embodiments, a display and/or alert may be generated based onthe fluctuation analysis. For instance, the fluctuation logic 198 maygenerate a graphic illustrating the detected fluctuation compared topreviously detected tip fluctuations and/or the anatomical movements ofthe patient body such as rhythmic pulses of the heart and/or expandingand contracting of the lungs. In one embodiment, such a graphic mayinclude a dynamic visualization of the present medical device moving inaccordance with the detected fluctuations adjacent to a secondarymedical device moving in accordance with previously detected tipfluctuations. In some embodiments, the location of a subsection of themedical device may be obtained from the shape sensing logic 194 and thedynamic visualization may be location-specific (e.g., such that thepreviously detected fluctuations illustrate expected fluctuations forthe current location of the subsection). In alternative embodiments, thedynamic visualization may illustrate a comparison of the dynamicmovements of the subsection to one or more subsections moving inaccordance with previously detected fluctuations of one or more defectsaffecting the blood vessel.

According to one embodiment of the disclosure, the fluctuation logic 198may determine whether movements of one or more subsections of the stylet120 indicate a location of a particular subsection of the stylet 120 ora defect affecting a blood vessel and, as a result, of the catheter 195,based on heuristics or run-time analytics. For example, the fluctuationlogic 198 may be configured in accordance with machine-learningtechniques to access a data store (library) with pre-stored data (e.g.,experiential knowledge of previously detected tip fluctuation data,etc.) pertaining to different regions (subsections) of the stylet 120.Specifically, such an embodiment may include processing of amachine-learning model trained using the experiential knowledge, wherethe detected fluctuations serve as input to the trained model andprocessing of the trained model results in a determination as to howclosely the detected fluctuations correlate to one or more locationswithin the vasculature of the patient and/or one or more defectsaffecting a blood vessel.

In some embodiments, the fluctuation logic 198 may be configured todetermine, during run-time, whether movements of one or more subsectionsof the stylet 120 (and the catheter 195) indicate a location of aparticular subsection of the stylet 120 or a defect affecting a bloodvessel, based on at least (i) resultant wavelength shifts experienced bythe core fibers 137 within the one or more subsections, and (ii) thecorrelation of these wavelength shifts generated by sensors positionedalong different core fibers at the same cross-sectional region of thestylet 120 (or the catheter 195) to previously detected wavelengthshifts generated by corresponding sensors in a core fiber at the samecross-sectional region. It is contemplated that other processes andprocedures may be performed to utilize the wavelength shifts as measuredby sensors along each of the core fibers 137 to render appropriatemovements in the distal tip of the stylet 120 and/or the catheter 195.

Referring to FIG. 1B, an alternative exemplary embodiment of a medicalinstrument monitoring system 100 is shown. Herein, the medicalinstrument monitoring system 100 features a console 110 and a medicalinstrument 130 communicatively coupled to the console 110. For thisembodiment, the medical instrument 130 corresponds to a catheter, whichfeatures an integrated tubing with two or more lumen extending between aproximal end 131 and a distal end 132 of the integrated tubing. Theintegrated tubing (sometimes referred to as “catheter tubing”) is incommunication with one or more extension legs 140 via a bifurcation hub142. An optical-based catheter connector 144 may be included on aproximal end of at least one of the extension legs 140 to enable thecatheter 130 to operably connect to the console 110 via an interconnect145 or another suitable component. Herein, the interconnect 145 mayinclude a connector 146 that, when coupled to the optical-based catheterconnector 144, establishes optical connectivity between one or moreoptical fibers 147 (hereinafter, “optical fiber(s)”) included as part ofthe interconnect 145 and core fibers 137 deployed within the catheter130 and integrated into the tubing. Alternatively, a differentcombination of connectors, including one or more adapters, may be usedto optically connect the optical fiber(s) 147 to the core fibers 137within the catheter 130. The core fibers 137 deployed within thecatheter 130 as illustrated in FIG. 1B include the same characteristicsand perform the same functionalities as the core fibers 137 deployedwithin the stylet 120 of FIG. 1A.

The optical logic 180 is configured to support graphical rendering ofthe catheter 130, most notably the integrated tubing of the catheter130, based on characteristics of the reflected light signals 150received from the catheter 130. The characteristics may include shiftsin wavelength caused by strain on certain regions of the core fibers 137integrated within (or along) a wall of the integrated tubing, which maybe used to determine (through computation or extrapolation of thewavelength shifts) the physical state of the catheter 130, notably itsintegrated tubing or a portion of the integrated tubing such as a tip ordistal end of the tubing to read fluctuations (real-time movement) ofthe tip (or distal end).

More specifically, the optical logic 180 includes a light source 182.The light source 182 is configured to transmit the broadband incidentlight 155 for propagation over the optical fiber(s) 147 included in theinterconnect 145, which are optically connected to multiple core fibers137 within the catheter tubing. Herein, the optical receiver 184 isconfigured to: (i) receive returned optical signals, namely reflectedlight signals 150 received from optical fiber-based reflective gratings(sensors) fabricated within each of the core fibers 137 deployed withinthe catheter 130, and (ii) translate the reflected light signals 150into reflection data (from repository 192), namely data in the form ofelectrical signals representative of the reflected light signalsincluding wavelength shifts caused by strain. The reflected lightsignals 150 associated with different spectral widths include reflectedlight signals 151 provided from sensors positioned in the center corefiber (reference) of the catheter 130 and reflected light signals 152provided from sensors positioned in the outer core fibers of thecatheter 130, as described below.

As noted above, the shape sensing logic 194 is configured to comparewavelength shifts measured by sensors deployed in each outer core fiberat the same measurement region of the catheter (or same spectral width)to the wavelength shift at the center core fiber positioned alongcentral axis and operating as a neutral axis of bending. From theseanalytics, the shape sensing logic 190 may determine the shape the corefibers have taken in 3D space and may further determine the currentphysical state of the catheter 130 in 3D space for rendering on thedisplay 170.

According to one embodiment of the disclosure, the shape sensing logic194 may generate a rendering of the current physical state of thecatheter 130, especially the integrated tubing, based on heuristics orrun-time analytics. For example, the shape sensing logic 194 may beconfigured in accordance with machine-learning techniques to access adata store (library) with pre-stored data (e.g., images, etc.)pertaining to different regions of the catheter 130 in which the corefibers 137 experienced similar or identical wavelength shifts. From thepre-stored data, the current physical state of the catheter 130 may berendered. Alternatively, as another example, the shape sensing logic 194may be configured to determine, during run-time, changes in the physicalstate of each region of the catheter 130, notably the tubing, based onat least (i) resultant wavelength shifts experienced by the core fibers137 and (ii) the relationship of these wavelength shifts generated bysensors positioned along different outer core fibers at the samecross-sectional region of the catheter 130 to the wavelength shiftgenerated by a sensor of the center core fiber at the samecross-sectional region. It is contemplated that other processes andprocedures may be performed to utilize the wavelength shifts as measuredby sensors along each of the core fibers 137 to render appropriatechanges in the physical state of the catheter 130.

Referring to FIG. 2, an exemplary embodiment of a structure of a sectionof the multi-core optical fiber included within the stylet 120 of FIG.1A is shown in accordance with some embodiments. The multi-core opticalfiber section 200 of the multi-core optical fiber 135 depicts certaincore fibers 137 ₁-137 M (M≥2, M=4 as shown, see FIG. 3A) along with thespatial relationship between sensors (e.g., reflective gratings) 210₁₁-210 _(NM) (N≥2; M≥2) present within the core fibers 137 ₁-137 M,respectively. As noted above, the core fibers 137 ₁-137 M may becollectively referred to as “the core fibers 137.”

As shown, the section 200 is subdivided into a plurality ofcross-sectional regions 220 ₁-220 _(N), where each cross-sectionalregion 220 ₁-220 _(N) corresponds to reflective gratings 210 ₁₁-210 ₁₄ .. . 210 _(N1)-210 _(N4). Some or all of the cross-sectional regions 220₁ . . . 220 _(N) may be static (e.g., prescribed length) or may bedynamic (e.g., vary in size among the regions 220 ₁ . . . 220 _(N)). Afirst core fiber 137 ₁ is positioned substantially along a center(neutral) axis 230 while core fiber 137 ₂ may be oriented within thecladding of the multi-core optical fiber 135, from a cross-sectional,front-facing perspective, to be position on “top” the first core fiber137 ₁. In this deployment, the core fibers 137 ₃ and 137 ₄ may bepositioned “bottom left” and “bottom right” of the first core fiber 137₁. As examples, FIGS. 3A-4B provides illustrations of such.

Referencing the first core fiber 137 ₁ as an illustrative example, whenthe stylet 120 is operative, each of the reflective gratings 210 ₁-210_(N) reflects light for a different spectral width. As shown, each ofthe gratings 210 _(1i)-210 _(Ni) (1≤i≤M) is associated with a different,specific spectral width, which would be represented by different centerfrequencies of ƒ₁ . . . ƒ_(N), where neighboring spectral widthsreflected by neighboring gratings are non-overlapping according to oneembodiment of the disclosure.

Herein, positioned in different core fibers 137 ₂-137 ₃ but along at thesame cross-sectional regions 220-220 _(N) of the multi-core opticalfiber 135, the gratings 210 ₁₂-210 _(N2) and 210 ₁₃-210 _(N3) areconfigured to reflect incoming light at same (or substantially similar)center frequency. As a result, the reflected light returns informationthat allows for a determination of the physical state of the opticalfibers 137 (and the stylet 120) based on wavelength shifts measured fromthe returned, reflected light. In particular, strain (e.g., compressionor tension) applied to the multi-core optical fiber 135 (e.g., at leastcore fibers 137 ₂-137 ₃) results in wavelength shifts associated withthe returned, reflected light. Based on different locations, the corefibers 137 ₁-137 ₄ experience different types and degree of strain basedon angular path changes as the stylet 120 advances in the patient.

For example, with respect to the multi-core optical fiber section 200 ofFIG. 2, in response to angular (e.g., radial) movement of the stylet 120is in the left-veering direction, the fourth core fiber 137 ₄ (see FIG.3A) of the multi-core optical fiber 135 with the shortest radius duringmovement (e.g., core fiber closest to a direction of angular change)would exhibit compression (e.g., forces to shorten length). At the sametime, the third core fiber 1373 with the longest radius during movement(e.g., core fiber furthest from the direction of angular change) wouldexhibit tension (e.g., forces to increase length). As these forces aredifferent and unequal, the reflected light from reflective gratings 210_(N2) and 210 _(N3) associated with the core fibers 137 ₂ and 137 ₃ willexhibit different changes in wavelength. The differences in wavelengthshift of the reflected light signals 150 can be used to extrapolate thephysical configuration of the stylet 120 by determining the degrees ofwavelength change caused by compression/tension for each of theperiphery fibers (e.g., the second core fiber 137 ₂ and the third corefiber 137 ₃) in comparison to the wavelength of the reference core fiber(e.g., first core fiber 137 ₁) located along the neutral axis 230 of themulti-core optical fiber 135. These degrees of wavelength change may beused to extrapolate the physical state of the stylet 120. The reflectedlight signals 150 are reflected back to the console 110 via individualpaths over a particular core fiber 137 ₁-137 _(M).

Referring to FIG. 3A, a first exemplary embodiment of the stylet of FIG.1A supporting both an optical and electrical signaling is shown inaccordance with some embodiments. Herein, the stylet 120 features acentrally located multi-core optical fiber 135, which includes acladding 300 and a plurality of core fibers 137 ₁-137 M (M≥2; M=4)residing within a corresponding plurality of lumens 320 ₁-320 _(M).While the multi-core optical fiber 135 is illustrated within four (4)core fibers 137 ₁-137 ₄, a greater number of core fibers 137 ₁-137 M(M>4) may be deployed to provide a more detailed three-dimensionalsensing of the physical state (e.g., shape, etc.) of the multi-coreoptical fiber 135 and the stylet 120 deploying the optical fiber 135.

For this embodiment of the disclosure, the multi-core optical fiber 135is encapsulated within a concentric braided tubing 310 positioned over alow coefficient of friction layer 335. The braided tubing 310 mayfeature a “mesh” construction, in which the spacing between theintersecting conductive elements is selected based on the degree ofrigidity desired for the stylet 120, as a greater spacing may provide alesser rigidity, and thereby, a more pliable stylet 120.

According to this embodiment of the disclosure, as shown in FIGS. 3A-3B,the core fibers 137 ₁-137 ₄ include (i) a central core fiber 137 ₁ and(ii) a plurality of periphery core fibers 137 ₂-137 ₄, which aremaintained within lumens 320 ₁-320 ₄ formed in the cladding 300.According to one embodiment of the disclosure, one or more of the lumen320 ₁-320 ₄ may be configured with a diameter sized to be greater thanthe diameter of the core fibers 137 ₁-137 ₄. By avoiding a majority ofthe surface area of the core fibers 137 ₁-137 ₄ from being in directphysical contact with a wall surface of the lumens 320 ₁-320 ₄, thewavelength changes to the incident light are caused by angulardeviations in the multi-core optical fiber 135 thereby reducinginfluence of compression and tension forces being applied to the wallsof the lumens 320 ₁-320 _(M), not the core fibers 137 ₁-137 Mthemselves.

As further shown in FIGS. 3A-3B, the core fibers 137 ₁-137 ₄ may includecentral core fiber 137 ₁ residing within a first lumen 320 ₁ formedalong the first neutral axis 230 and a plurality of core fibers 137₂-137 ₄ residing within lumens 320 ₂-320 ₄ each formed within differentareas of the cladding 300 radiating from the first neutral axis 230. Ingeneral, the core fibers 137 ₂-137 ₄, exclusive of the central corefiber 137 ₁, may be positioned at different areas within across-sectional area 305 of the cladding 300 to provide sufficientseparation to enable three-dimensional sensing of the multi-core opticalfiber 135 based on changes in wavelength of incident light propagatingthrough the core fibers 137 ₂-137 ₄ and reflected back to the consolefor analysis.

For example, where the cladding 300 features a circular cross-sectionalarea 305 as shown in FIG. 3B, the core fibers 137 ₂-137 ₄ may bepositioned substantially equidistant from each other as measured along aperimeter of the cladding 300, such as at “top” (12 o'clock),“bottom-left” (8 o'clock) and “bottom-right” (4 o'clock) locations asshown. Hence, in general terms, the core fibers 137 ₂-137 ₄ may bepositioned within different segments of the cross-sectional area 305.Where the cross-sectional area 305 of the cladding 300 has a distal tip330 and features a polygon cross-sectional shape (e.g., triangular,square, rectangular, pentagon, hexagon, octagon, etc.), the central corefiber 137 ₁ may be located at or near a center of the polygon shape,while the remaining core fibers 137 ₂-137 M may be located proximate toangles between intersecting sides of the polygon shape.

Referring still to FIGS. 3A-3B, operating as the conductive medium forthe stylet 120, the braided tubing 310 provides mechanical integrity tothe multi-core optical fiber 135 and operates as a conductive pathwayfor electrical signals. For example, the braided tubing 310 may beexposed to a distal tip of the stylet 120. The cladding 300 and thebraided tubing 310, which is positioned concentrically surrounding acircumference of the cladding 300, are contained within the sameinsulating layer 350. The insulating layer 350 may be a sheath orconduit made of protective, insulating (e.g., non-conductive) materialthat encapsulates both for the cladding 300 and the braided tubing 310,as shown.

Referring to FIG. 4A, a second exemplary embodiment of the stylet ofFIG. 1A is shown in accordance with some embodiments. Referring now toFIG. 4A, a second exemplary embodiment of the stylet 120 of FIG. 1Asupporting both an optical and electrical signaling is shown. Herein,the stylet 120 features the multi-core optical fiber 135 described aboveand shown in FIG. 3A, which includes the cladding 300 and the firstplurality of core fibers 137 ₁-137 M (M≥3; M=4 for embodiment) residingwithin the corresponding plurality of lumens 320 ₁-320 _(M). For thisembodiment of the disclosure, the multi-core optical fiber 135 includesthe central core fiber 137 ₁ residing within the first lumen 320 ₁formed along the first neutral axis 230 and the second plurality of corefibers 137 ₂-137 ₄ residing within corresponding lumens 320 ₂-320 ₄positioned in different segments within the cross-sectional area 305 ofthe cladding 300. Herein, the multi-core optical fiber 135 isencapsulated within a conductive tubing 400. The conductive tubing 400may feature a “hollow” conductive cylindrical member concentricallyencapsulating the multi-core optical fiber 135.

Referring to FIGS. 4A-4B, operating as a conductive medium for thestylet 120 in the transfer of electrical signals (e.g., ECG signals) tothe console, the conductive tubing 400 may be exposed up to a tip 410 ofthe stylet 120. For this embodiment of the disclosure, a conductiveepoxy 420 (e.g., metal-based epoxy such as a silver epoxy) may beaffixed to the tip 410 and similarly joined with atermination/connection point created at a proximal end 430 of the stylet120. The cladding 300 and the conductive tubing 400, which is positionedconcentrically surrounding a circumference of the cladding 300, arecontained within the same insulating layer 440. The insulating layer 440may be a protective conduit encapsulating both for the cladding 300 andthe conductive tubing 400, as shown.

Referring to FIG. 5A, an elevation view of a first illustrativeembodiment of a catheter including integrated tubing, a diametricallydisposed septum, and micro-lumens formed within the tubing and septum isshown in accordance with some embodiments. Herein, the catheter 130includes integrated tubing, the diametrically disposed septum 510, andthe plurality of micro-lumens 530 ₁-530 ₄ which, for this embodiment,are fabricated to reside within the wall 500 of the integrated tubing ofthe catheter 130 and within the septum 510. In particular, the septum510 separates a single lumen, formed by the inner surface 505 of thewall 500 of the catheter 130, into multiple lumen, namely two lumens 540and 545 as shown. Herein, the first lumen 540 is formed between a firstarc-shaped portion 535 of the inner surface 505 of the wall 500 formingthe catheter 130 and a first outer surface 555 of the septum 510extending longitudinally within the catheter 130. The second lumen 545is formed between a second arc-shaped portion 565 of the inner surface505 of the wall 500 forming the catheter 130 and a second outer surfaces560 of the septum 510.

According to one embodiment of the disclosure, the two lumens 540 and545 have approximately the same volume. However, the septum 510 need notseparate the tubing into two equal lumens. For example, instead of theseptum 510 extending vertically (12 o'clock to 6 o'clock) from afront-facing, cross-sectional perspective of the tubing, the septum 510could extend horizontally (3 o'clock to 9 o'clock), diagonally (1o'clock to 7 o'clock; 10 o'clock to 4 o'clock) or angularly (2 o'clockto 10 o'clock). In the later configuration, each of the lumens 540 and545 of the catheter 130 would have a different volume.

With respect to the plurality of micro-lumens 530 ₁-530 ₄, the firstmicro-lumen 530 ₁ is fabricated within the septum 510 at or near thecross-sectional center 525 of the integrated tubing. For thisembodiment, three micro-lumens 530 ₂-530 ₄ are fabricated to residewithin the wall 500 of the catheter 130. In particular, a secondmicro-lumen 530 ₂ is fabricated within the wall 500 of the catheter 130,namely between the inner surface 505 and outer surface 507 of the firstarc-shaped portion 535 of the wall 500. Similarly, the third micro-lumen530 ₃ is also fabricated within the wall 500 of the catheter 130, namelybetween the inner and outer surfaces 505/507 of the second arc-shapedportion 555 of the wall 500. The fourth micro-lumen 530 ₄ is alsofabricated within the inner and outer surfaces 505/507 of the wall 500that are aligned with the septum 510.

According to one embodiment of the disclosure, as shown in FIG. 5A, themicro-lumens 530 ₂-530 ₄ are positioned in accordance with a “top-left”(10 o'clock), “top-right” (2 o'clock) and “bottom” (6 o'clock) layoutfrom a front-facing, cross-sectional perspective. Of course, themicro-lumens 530 ₂-530 ₄ may be positioned differently, provided thatthe micro-lumens 530 ₂-530 ₄ are spatially separated along thecircumference 520 of the catheter 130 to ensure a more robust collectionof reflected light signals from the outer core fibers 570 ₂-570 ₄ wheninstalled. For example, two or more of micro-lumens (e.g., micro-lumens530 ₂ and 530 ₄) may be positioned at different quadrants along thecircumference 520 of the catheter wall 500.

Referring to FIG. 5B, a perspective view of the first illustrativeembodiment of the catheter of FIG. 5A including core fibers installedwithin the micro-lumens is shown in accordance with some embodiments.According to one embodiment of the disclosure, the second plurality ofmicro-lumens 5302-5304 are sized to retain corresponding outer corefibers 570 ₂-570 ₄, where the diameter of each of the second pluralityof micro-lumens 530 ₂-530 ₄ may be sized just larger than the diametersof the outer core fibers 570 ₂-570 ₄. The size differences between adiameter of a single core fiber and a diameter of any of the micro-lumen530 ₁-530 ₄ may range between 0.001 micrometers (μm) and 1000 μm, forexample. As a result, the cross-sectional areas of the outer core fibers570 ₂-570 ₄ would be less than the cross-sectional areas of thecorresponding micro-lumens 530 ₂-530 ₄. A “larger” micro-lumen (e.g.,micro-lumen 530 ₂) may better isolate external strain being applied tothe outer core fiber 570 ₂ from strain directly applied to the catheter130 itself. Similarly, the first micro-lumen 530 ₁ may be sized toretain the center core fiber 570 ₁, where the diameter of the firstmicro-lumen 530 ₁ may be sized just larger than the diameter of thecenter core fiber 570 ₁.

As an alternative embodiment of the disclosure, one or more of themicro-lumens 530 ₁-530 ₄ may be sized with a diameter that exceeds thediameter of the corresponding one or more core fibers 570 ₁-570 ₄.However, at least one of the micro-lumens 530 ₁-530 ₄ is sized tofixedly retain their corresponding core fiber (e.g., core fiber retainedwith no spacing between its lateral surface and the interior wallsurface of its corresponding micro-lumen). As yet another alternativeembodiment of the disclosure, all the micro-lumens 530 ₁-530 ₄ are sizedwith a diameter to fixedly retain the core fibers 570 ₁-570 ₄.

Referring to FIGS. 6A-6B, flowcharts of methods of operations conductedby the medical instrument monitoring system of FIGS. 1A-1B to achieveoptic 3D shape sensing are shown in accordance with some embodiments.Herein, the catheter includes at least one septum spanning across adiameter of the tubing wall and continuing longitudinally to subdividethe tubing wall. The medial portion of the septum is fabricated with afirst micro-lumen, where the first micro-lumen is coaxial with thecentral axis of the catheter tubing. The first micro-lumen is configuredto retain a center core fiber. Two or more micro-lumen, other than thefirst micro-lumen, are positioned at different locationscircumferentially spaced along the wall of the catheter tubing. Forexample, two or more of the second plurality of micro-lumens may bepositioned at different quadrants along the circumference of thecatheter wall.

Furthermore, each core fiber includes a plurality of sensors spatiallydistributed along its length between at least the proximal and distalends of the catheter tubing. This array of sensors is distributed toposition sensors at different regions of the core fiber to enabledistributed measurements of strain throughout the entire length or aselected portion of the catheter tubing. These distributed measurementsmay be conveyed through reflected light of different spectral widths(e.g., specific wavelength or specific wavelength ranges) that undergoescertain wavelength shifts based on the type and degree of strain.

According to one embodiment of the disclosure, as shown in FIG. 6A, foreach core fiber, broadband incident light is supplied to propagatethrough a particular core fiber (block 600). Unless discharged, upon theincident light reaching a sensor of a distributed array of sensorsmeasuring strain on a particular core fiber, light of a prescribedspectral width associated with the first sensor is to be reflected backto an optical receiver within a console (blocks 605-610). Herein, thesensor alters characteristics of the reflected light signal to identifythe type and degree of strain on the particular core fiber as measuredby the first sensor (blocks 615-620). According to one embodiment of thedisclosure, the alteration in characteristics of the reflected lightsignal may signify a change (shift) in the wavelength of the reflectedlight signal from the wavelength of the incident light signal associatedwith the prescribed spectral width. The sensor returns the reflectedlight signal over the core fiber and the remaining spectrum of theincident light continues propagation through the core fiber toward adistal end of the catheter tubing (blocks 625-630). The remainingspectrum of the incident light may encounter other sensors of thedistributed array of sensors, where each of these sensors would operateas set forth in blocks 605-630 until the last sensor of the distributedarray of sensors returns the reflected light signal associated with itsassigned spectral width and the remaining spectrum is discharged asillumination.

Referring now to FIG. 6B, during operation, multiple reflected lightsignals are returned to the console from each of the plurality of corefibers residing within the corresponding plurality of micro-lumensformed within a catheter, such as the catheter of FIG. 1B. Inparticular, the optical receiver receives reflected light signals fromthe distributed arrays of sensors located on the center core fiber andthe outer core fibers and translates the reflected light signals intoreflection data, namely electrical signals representative of thereflected light signals including wavelength shifts caused by strain(blocks 650-655). The reflection data classification logic is configuredto identify which core fibers pertain to which reflection data andsegregate reflection data provided from reflected light signalspertaining to a particular measurement region (or similar spectralwidth) into analysis groups (block 660-665).

Each analysis group of reflection data is provided to shape sensinglogic for analytics (block 670). Herein, the shape sensing logiccompares wavelength shifts at each outer core fiber with the wavelengthshift at the center core fiber positioned along central axis andoperating as a neutral axis of bending (block 675). From this analytics,on all analytic groups (e.g., reflected light signals from sensors inall or most of the core fibers), the shape sensing logic may determinethe shape the core fibers have taken in three-dimensional space, fromwhich the shape sensing logic can determine the current physical stateof the catheter in three-dimension space (blocks 680-685).

Referring to FIG. 7, an exemplary embodiment of the medical instrumentmonitoring system of FIG. Al during operation and insertion of thecatheter into a patient are shown in accordance with some embodiments.Herein, the catheter 195 generally includes integrated tubing with aproximal portion 720 that generally remains exterior to the patient 700and a distal portion 730 that generally resides within the patientvasculature after placement is complete, where the catheter 195 entersthe vasculature at insertion site 710. The stylet 120 may be advancedthrough the catheter 195 to a desired position within the patientvasculature such that a distal end (or tip) 735 of the stylet 120 (andhence a distal end of the catheter 195) is proximate the patient'sheart, such as in the lower one-third (⅓) portion of the Superior VenaCava (“SVC”) for example. For this embodiment, various instruments maybe placed at the distal end 735 of the stylet 120 and/or the catheter195 to measure pressure of blood in a certain heart chamber and in theblood vessels, view an interior of blood vessels, or the like.

During advancement through a patient vasculature, the stylet 120receives broadband incident light 155 from the console 110 via opticalfiber(s) 147 within the interconnect 145, where the incident light 155propagates to the core fibers 137 within the stylet 120. According toone embodiment of the disclosure, the connector 146 of the interconnect145 terminating the optical fiber(s) 147 may be coupled to theoptical-based catheter connector 144, which may be configured toterminate the core fibers 137 deployed within the stylet 120. Suchcoupling optically connects the core fibers 137 of the stylet 120 withthe optical fiber(s) 147 within the interconnect 145. The opticalconnectivity is needed to propagate the incident light 155 to the corefibers 137 and return the reflected light signals 150 to the opticallogic 180 within the console 110 over the interconnect 145. The physicalstate of the stylet 120 may be ascertained based on analytics of thewavelength shifts of the reflected light signals 150.

Referring now to FIG. 8, an embodiment of a structure of a section of asingle core optical fiber included within a stylet 800 that is kinked ordamaged is shown in accordance with some embodiments. The single coreoptical fiber section 801 of the optical fiber 836 depicts a singularcore fiber 837 along with the spatial relationship between sensors(e.g., reflective gratings) 810 ₁-810 _(N) (N≥2) present within the corefiber. As shown, the single core optical fiber 836 included within astylet 800 is similar to the multi-core optical fiber section 200 ofFIG. 2, such that the discussion about regarding the functionality ofthe sensors (reflective gratings) 210 ₁₁-210 _(NM) (N≥2; M≥2) presentwithin the core fibers 137 ₁-137 _(M), respectively of FIG. 2, appliesto the reflective gratings 810 ₁-810 _(N) present within the core fiber837. For instance, the single core optical fiber section 801 issubdivided into a plurality of cross-sectional regions 820 ₁-820 _(N),where each cross-sectional region 820 ₁-820 _(N) corresponds to areflective grating 810 ₁-810 _(N). Some or all of the cross-sectionalregions 820 ₁ . . . 820 _(N) may be static (e.g., prescribed length) ormay be dynamic (e.g., vary in size among the regions 820 ₁ . . . 820_(N)).

The core fiber 837 is positioned substantially along a center axis 830within the cladding of the single core optical fiber 836. When stylet800 is operative, each of the reflective gratings 810 ₁-810 _(N)reflects light for a different spectral width. As shown, each of thegratings 810 ₁-810 _(N) is associated with a different, specificspectral width, which would be represented by different centerfrequencies of ƒ₁ . . . ƒ_(N), where neighboring spectral widthsreflected by neighboring gratings are non-overlapping according to oneembodiment of the disclosure.

As a result, the reflected light returns information that allows for adetermination of the physical state of the single core optical fiber 836(and the stylet 800) based on wavelength shifts measured from thereturned, reflected light. In particular, strain (e.g., compression ortension) applied to the single core optical fiber 836 results inwavelength shifts associated with the returned, reflected light. Basedon different locations, the core fiber 837 experiences different typesand degree of strain based on angular path changes as the stylet 800advances in the patient.

In a healthy, operative state, the reflective gratings 810 ₁-810 _(N)receive broadband incident land 155 and reflect light having differentspectral widths such that logic of the console 110 may determine aphysical state of the single core optical fiber 836 (and the stylet800). However, when damage occurs to the single core optical fiber 836or a kink develops, the receipt of the incident light 155 by each of thereflective gratings 810 ₁-810 _(N) and the corresponding reflection oflight signals may be impaired, preventing the logic of the console 110from determining the physical state of the single core optical fiber 836(and the stylet 800). In some instances, the incident light 155 isunable to propagate beyond the damage.

In particular, FIG. 8 illustrates the single core optical fiber 836following an occurrence of damage resulting in damage 840. Examples ofdamage may include, but are not limited or restricted to, cracking ofthe core fiber (excess tension, e.g., during cable pulling ordespoiling) or bending of the core fiber on too tight of a radius(excess tension or excess compression). In some instances, excessivelybending a core fiber (i.e., bending beyond the core fiber bend radius)may also cause micro-cracks in the core fiber resulting in permanentdamage, which may result in a reflected wavelength peak overlapdegrading the ability for the logic to determine the shape of the corefiber.

As shown, the damage 840 is present within the cross-sectional region820 ₂ at a location that is proximal the reflective gratings 810 ₂-810_(N). The damage 840 may alter the incident light 155 that propagatesbeyond the damage 840 (resulting in propagation of the altered incidentlight 156) or prevent light from passing to a location distal the damage840 (i.e., due to a complete break or fracture).

As a result, the console 110 may receive reflected light signals 842₁-842 _(N), where one or more of the reflected light signals 842 ₂-842_(N) are have unexpected spectral widths due to the altered incidentlight 156, and/or may not receive reflected light signals from one ormore of the reflective gratings 810 ₂-810 _(N) due to the inability of areflective grating to reflect the altered incident light 156. Inembodiments in which incident light is prevented from propagating beyondthe damage 840, reflected light signals will only be received fromreflective gratings that are proximal the damage 840 (e.g., thereflective grating 810 ₁). As a result of the damage 840, the logic ofthe console 110 is unable to determine a physical state of the singlecore optical fiber 836 (or the stylet 800) for at least the portion ofthe single core optical fiber 836 comprised of the cross-sectionalregions 820 ₂-820 _(N).

When the console 110 receives the reflected light signal 842 ₁ and, ininstances when the altered incident light 156 propagates beyond thedamage 840, one or more of reflected light signals 842 ₂-842 _(N), theoptical receiver 184 processes the received reflected light signals andprovides such to the reflection data classification logic 190, whichfurther processes the received reflected light signals as discussedabove. The core fiber health detection logic 191 may then analyzereceived reflected light signals for unexpected spectral widths (eachreflective grating is configured to reflect incident light at a specificspectral width) or for a lack of receipt of one or more expectedspectral widths. Thus, when one or more of the reflected light signals842 ₂-842 _(N) are received, each includes unexpected spectral widths(i.e., not matching those assigned to each of the reflective gratings810 ₂-810 _(N)), the core fiber health detection logic 191 determinesthat damage has occurred to the core fiber 837.

Further, in some embodiments, the specific spectral width of eachreceived reflected light signal may be analyzed to determine a locationalong the core fiber 837 at which damage (or a kink) occurred.Specifically, the core fiber health detection logic 191 may furtheranalyze each of the received light signals to identify (i) a most distalreflective grating from which a normal, uncorrupted light signal wasreceived, and a (ii) a most proximal reflective grating from which acorrupted (e.g., degraded) light signal was received. Such anidentification of reflective gratings results in an identification ofthe location of the kink or point of damage. Thus, by determining thatthe most distal reflective grating from which a reflected light signalhaving an expected spectral width was received is the reflective grating810 ₁ and the most proximal reflective grating from which a reflectedlight signal having an unexpected spectral width was received is thereflective grating 810 ₂, the core fiber health detection logic 191identifies the location of the damage 840 (i.e., between the reflectivegratings 810 ₁ and 810 ₂). In embodiments in which the incident light155 is prevented from propagating beyond the damage 840, the location ofthe damage 840 is determined to be based on the lack of reflected lightsignals received from any of 810 ₂-810 _(N).

In some embodiments, the core fiber health detection logic 191 may beconfigured to generate an alert indicating that the optical fiber 836has been damaged, and, optionally, identifying the location of thedamage. The alert may be provided or rendered by the console 110, ortransmitted to an alternative electronic device (e.g., a speaker ordisplay not integrated into the console 110, a network device such as amobile device, etc.). For example, the alert may be an audio/visualindication that damage has occurred. In some embodiments, the alert maybe generated by a separate logic module, such an as alert generationlogic (not shown).

In some embodiments, the core fiber health detection logic 191 may alsobe configured to analyze each of the received light signals to identifyparticular strain detected by reflective gratings. The identified strainmay be compared to previously identified strain that corresponds topositioning or a shape of the core fiber 137 that has a high likelihoodof resulting in damage to the core fiber 137. The information pertainingto the previously identified strain may be stored as part of thereflection data 192. In some embodiments, the core fiber healthdetection logic 191 may operate in combination with the shape sensinglogic 192 in identifying shapes of the core fiber 137 (e.g., the corefiber health detection logic 191 may compare a shape of the core fiber137 against stored shapes known to have a high likelihood of causingdamage to the core fiber 137). Thus, the core fiber health detectionlogic 191 may analyze received light signals to determine whether thecurrent shape of the core fiber 137 (or stylet or catheter within whichthe core fiber 137 is disposed or otherwise affixed) is within athreshold percentage of matching a shape known to have a high likelihoodof causing damage. More broadly, the core fiber health detection logic191 may analyze received light signals to determine whether the straincurrently being experienced by the core fiber 137 (or stylet or catheterwithin which the core fiber 137 is disposed or otherwise affixed) iswithin a threshold percentage of matching strain known to have a highlikelihood of causing damage. When the shape or strain of the core fiber137 is similar to a shape or strain known to have a high likelihood ofcausing damage, the core fiber health detection logic 191 may cause analert to be generated. In some embodiments, being “similar to a shape orstrain” may refer to the identified shape or strain being within athreshold percentage of matching a shape or strain known to have a highlikelihood of causing damage

In embodiments, the core fiber health detection logic 191 may alsoextrapolate the reflection data of a core fiber 137 to predict a futureshape (and corresponding strain) of the core fiber 137. When theextrapolated shape or strain of the core fiber 137 is similar to a shapeor strain known to have a high likelihood of causing damage, the corefiber health detection logic 191 may cause an alert to be generated. Insome embodiments, being “similar to a shape or strain” may refer to theextrapolated shape or strain being within a threshold percentage ofmatching a shape or strain known to have a high likelihood of causingdamage. Further, the core fiber health detection logic 191 may perform asimilar analysis on the received light signals to determine whether astylet and/or catheter within which the core fiber is disposed (orotherwise affixed) is currently in a shape or be experiencing strainknown to have a high likelihood of causing damage. Similarly, the corefiber health detection logic 191 may perform a similar analysis on thereceived light signals to determine whether a stylet and/or catheterwithin which the core fiber is disposed (or otherwise affixed) hasprolapsed.

Referring to FIG. 9A, an embodiment of the structure of the section ofthe multi-core optical fiber of FIG. 2 included within the stylet 120 ofFIG. 1A that is kinked or partially damaged is shown in accordance withsome embodiments. As discussed previously, the multi-core optical fibersection 200 of the optical fiber core 136 depicts certain core fibers137 ₁-137 ₄ along with the spatial relationship between sensors 210₁₁-210 _(NM) present within the core fibers 137 ₁-137 ₄, respectively.As shown, the section 200 is subdivided into a plurality ofcross-sectional regions 220 ₁-220 _(N), where each cross-sectionalregion 220 ₁-220 _(N) corresponds to reflective gratings 210 ₁₁-210 ₁₄ .. . 210 _(N1)-210 _(N4).

However, differently than FIG. 2, FIG. 9A illustrates the multi-coreoptical fiber section 200 including damage 900, where the damage 900affects the core fiber 137 ₂ within the cross-sectional region 2202between the reflective grating 210 ₁₂ and the reflective grating 210 ₂₂.The damage 900 may a result of one or more various factors includingkinking and/or excess strain (compression or tension) placed on the corefiber 137 ₂. Additionally, or in the alternatively, blunt physical forceincurred by the core fiber 137 ₂ may result in the damage 900. Detectionof the damage 900 is beneficial such that an alert may be generatednotifying a user of such. For example, a physician improperly trimming acatheter without pulling back a stylet including an optical fiber wouldbe immediately notified through generation of an alert that theirpractice is impacting system functionality.

As shown in the illustration, the incident light 155 propagates alongthe length of each of the core fibers 137 ₁-137 ₄ such that reflectivegratings disposed thereon may reflect light signals back to the console110. However, in some instances, the damage 900 may affect the incidentlight propagating along the length of the core fiber 137 ₂ such thataltered incident light 156 propagated along the length of the core fiber137 ₂ distal the point along the core fiber 137 ₂ at which the damage900 occurred (“point of damage 900”). The altered incident 156 light maybe degraded or altered in any manner, which may affect the ability ofthe reflective gratings 210 ₂₂-210 _(N2) from reflecting light signalsin accordance with the applied strain on the correspondingcross-sectional region. In some embodiments, the incident light 155 isunable to propagate past the damage 900 altogether.

More specifically, the damage 900 causes an alteration in the incidentlight 155 propagating along the core fiber 137 ₂ resulting in thealtered incident light 156 to propagate distal the damage 900, where thealtered incident 156 may be a portion of incident light 155. Thereflected light signal 902 is reflected by one or more of the reflectivegratings distal the damage 900 (i.e., reflective gratings 210 ₂₂-210_(N2)), wherein the reflected light signal 902 includes reflected lightsignals having unexpected spectral widths. In some instances, thereflected light signal 902 includes reflected light signals from lessthan all of the reflective gratings 210 ₂₂-210 _(N2)) (i.e., one or moreof the reflective gratings 210 ₂₂-210 _(N2) did not reflect a lightsignal). In some embodiments, the damage 900 may be a complete breakageor fracture of the core fiber 1372 such that no portion of the incidentlight 155 is able propagate past the damage 900. In such instances, thereflective gratings 210 ₂₂-210 _(N2) would not reflect the reflectedlight signal 902.

Upon receipt of the reflected light signals 152 ₁-152 ₄ and 902 by theconsole 110, the optical receiver 184 processes the received reflectedlight signals and provides such to the reflection data classificationlogic 190, which further processes the received reflected light signalsas discussed above. The core fiber health detection logic 191 may thenanalyze received reflected light signals corresponding to each corefiber 137 ₁-137 ₄. In one embodiment, each core fiber 137 ₁-137 ₄ isassigned with a unique identifier (ID) to which each reflected lightsignal is associated. Thus, association of a reflected light signal witha specific core fiber 137 ₁-137 ₄ is maintained via the unique ID ofeach core fiber 137 ₁-137 ₄.

Specifically, detection of damage to a core fiber 137 ₁-137 _(i) isperformed by analyzing the received reflected light signals 152 ₁-152 ₄and 902 for unexpected spectral widths (each reflective grating isconfigured to reflect incident light at a specific spectral width) orfor a lack of receipt of one or more expected spectral widths. Thus, asthe reflected light signal 902 includes unexpected spectral widths(i.e., not matching those assigned to each of the reflective gratings210 ₂₂-210 _(N2)), the core fiber health detection logic 191 determinesthat damage has occurred to the core fiber 137 ₂.

Further, in some embodiments, the specific spectral width of eachreceived reflected light signal may be analyzed to determine a locationalong the core fiber 137 ₂ at which damage (or a kink) occurred. As thecore fiber health detection logic 191 (or more generally, the reflectiondata classification logic 190) determined that the unexpected spectralwidth within the received light signal 902 was received from the corefiber 137 ₂, the core fiber health detection logic 191 may furtheranalyze each of the received light signals 152 ₂ and 902 to identify (i)a most distal reflective grating from which a normal, uncorrupted lightsignal was received, and a (ii) a most proximal reflective grating fromwhich a corrupted (e.g., degraded) light signal was received. Such anidentification of reflective gratings results in an identification ofthe location of the kink or point of damage. Thus, by determining thatthe most distal reflective grating from which a reflected light signalhaving an expected spectral width was received is the reflective grating210 ₁₂ and the most proximal reflective grating from which a reflectedlight signal having an unexpected spectral width was received is thereflective grating 210 ₂₂, the core fiber health detection logic 191identifies the location of the damage 900 (i.e., between the reflectivegratings 210 ₁₂ and 210 ₂₂).

Although damage may degrade or otherwise alter the operability of one ormore core fibers, optical fibers that include redundant core fibers maymaintain complete or partial functionality beyond the point of damage.As illustrated in FIG. 9A, the core fiber 137 ₂ is shown to be damagedwithin the cross-sectional region 220 ₂ while the core fibers 137 ₁ and137 ₃-137 ₄ have not incurred damaged; thus, some functionality of themulti-core optical fiber 136 may be maintained via reflected signalsreceived from the core fibers 137 ₁ and 137 ₃-137 ₄.

For example, in some embodiments, a stylet may be configured to performseveral measurements and/or take several readings during advancementthrough a catheter lumen, such that the measurements and readings areprovided to logic of a console, such as the console 110, for processing.For example, a multi-core optical fiber may be integrated within thestylet along with one or more pulse oximetry sensors and/or one or moreelectrodes for intravascular electrocardiogram (ECG) monitoring. Such astylet provides measurements and readings to the console 110 foranalyses that determine a physical state (e.g., shape) of the stylet,whether the distal tip of the stylet has entered the Azygos vein, anamount of fluctuation of the distal tip of the stylet, a level of oxygenin the patient's blood, and location tracking of the distal tip of thestylet via ECG monitoring. In instances in which one or more core fibersof the multi-core optical fiber are damaged, the stylet is stilloperable obtain measurements and/or readings pertaining to one or moreof the functionalities described above. For example, in the even thatone or more core fibers are damaged, the stylet may still be functionalto provide information pertaining to whether the distal tip of thestylet has entered the Azygos vein, an amount of fluctuation of thedistal tip of the stylet, a level of oxygen in the patient's blood, andlocation tracking of the distal tip of the stylet via ECG monitoring.

One or more embodiments of the disclosure may include a body ofimplementation configured to perform any combination of the followingfunctions: fiber optic fluctuation sensing/monitoring, fiber optic shapesensing, fiber optic oximetry monitoring, distal tip placementconfirmation, distal tip location/tracking, Azygos vein detection,impedance/conductance sensing, intravascular ECG monitoring, and/orfiber optic vein/artery cannulation detection. As discussed above, sucha body of implementation is configured to maintain the ability toperform one or more of these functionalities when one or more of thecore fibers of the multi-core optical fiber integrated into the body ofimplementation are damaged or kinked such and non-functional past thekink or point of damage.

Additionally, the multi-core optical fiber 136 may include a number ofcore fibers greater than illustrated in the figures included herein,which may provide sufficient redundancy to maintain the shape sensingfunctionality past the point of damage. In order to maintain the abilityto perform shape sensing past the point of damage, the number ofoperable core fibers (i.e., those capable of receiving incident lightand reflecting light signals to the console 110 without such adegradation that prevents the shape sensing logic 194 from determiningthe physical state of the stylet/catheter with a level of confidence).As one exemplary embodiment, a multi-core optical fiber having seven ormore core fibers would include sufficient redundancy to maintain shapesensing functionalities past a point of damage when one of the sevencore fibers is non-functional past the point of damage.

In some embodiments, however, an optical fiber may not includesufficient redundancy in order to preserve shape sensing capabilitiesdue to damage. For example, with reference to FIG. 9A that includes fourperiphery cores and one central core, damage at a periphery core wouldnot maintain shape sensing capabilities. However, damage to only thecentral core with four properly functioning periphery cores would haveredundant shape sensing capability.

Referring to FIG. 9B, an embodiment of a structure of a section of amulti-core optical fiber included within the stylet 120 of FIG. 1A thatis completely damaged is shown in accordance with some embodiments. Inthe same manner as discussed above with respect to FIG. 9A, the corefiber health detection logic 191 analyzes reflected light signals 906₁-906 ₄ for unexpected spectral widths (or a lack of expected spectralwidths).

Thus, as the reflected light signal 152 ₁-152 ₄ and 906 ₁-906 ₄ forinclude unexpected spectral widths (i.e., not matching those assigned toeach of the reflective gratings 210 ₁₁-210 ₁₄ . . . 210 _(N1)-210_(N4).), the core fiber health detection logic 191 determines thatdamage 904 has occurred affecting each of the core fibers 137 ₁-137 ₄.

As also discussed above with respect to FIG. 9A, the specific spectralwidth of each received reflected light signal may be analyzed todetermine a location along the core fibers 137 ₁-137 ₄ at which thedamage (or a kink) occurred. The core fiber health detection logic 191may further analyze each of the reflected light signals 152 ₁-152 ₄ and906 ₁-906 ₄ to identify (i) a most distal reflective grating from whicha normal, uncorrupted light signal was received, and a (ii) a mostproximal reflective grating from which a corrupted (e.g., degraded)light signal was received. Thus, by determining that the most distalreflective grating from which a reflected light signal having anexpected spectral width was received is the reflective gratings 210 ₁₁,210 ₁₂, 210 ₁₃ and 210 ₁₄ (referring to the core fibers 137 ₁-137 ₄,respectively) and the most proximal reflective grating from which areflected light signal having an unexpected spectral width was receivedis the reflective gratings 210 ₂₁, 210 ₂₂, 210 ₂₃ and 210 ₂₄ (referringto the core fibers 137 ₁-137 ₄, respectively), the core fiber healthdetection logic 191 identifies the location of the damage 904.

Although damage may degrade or otherwise alter the operability of one ormore core fibers, optical fibers that include redundant core fibers maymaintain complete or partial functionality beyond the point of damage.As illustrated in FIG. 9A, the core fiber 137 ₂ is shown to be damagedwithin the cross-sectional region 2202 while the core fibers 137 ₁ and137 ₃-137 ₄ have not incurred damaged; thus, some functionality of themulti-core optical fiber 136 may be maintained via reflected signalsreceived from the core fibers 137 ₁ and 137 ₃-137 ₄.

It should be understood that in instances in which the damage 904 is acomplete break or fracture such that no incident light 155 propagatesbeyond the damage 904, the reflected light signals 906 ₁-906 ₄ do notexist.

While some particular embodiments have been disclosed herein, and whilethe particular embodiments have been disclosed in some detail, it is notthe intention for the particular embodiments to limit the scope of theconcepts provided herein. Additional adaptations and/or modificationscan appear to those of ordinary skill in the art, and, in broaderaspects, these adaptations and/or modifications are encompassed as well.Accordingly, departures may be made from the particular embodimentsdisclosed herein without departing from the scope of the conceptsprovided herein.

1. A medical device system for detecting damage to an optical fibertechnology of a medical device, the system comprising: the medicaldevice comprising an optical fiber having one or more of core fibers,each of the one or more core fibers including a plurality of sensorsdistributed along a longitudinal length of a corresponding core fiberand each sensor of the plurality of sensors being configured to (i)reflect a light signal of a different spectral width based on receivedincident light, and (ii) change a characteristic of the reflected lightsignal for use in determining a physical state of the optical fiber; anda console including one or more processors and a non-transitorycomputer-readable medium having stored thereon logic, when executed bythe one or more processors, causes operations including: providing abroadband incident light signal to the optical fiber; receivingreflected light signals of different spectral widths of the broadbandincident light by one or more of the plurality of sensors; processingthe reflected light signals associated with the one or more of corefibers to identify at least one unexpected spectral width or a lack ofan expected spectral width; and determining the damage has occurred toone or more of the core fibers based on identification of the at leastone unexpected spectral width, a lack of an expected spectral width, ora reduction in intensity of a reflected light signal.
 2. The system ofclaim 1, wherein an unexpected spectral width is a spectral width notconfigured for use by any of the plurality of sensors of a core fiber.3. The system of claim 1, wherein the optical fiber is a single-coreoptical fiber.
 4. The system of claim 1, wherein the optical fiber is amulti-core optical fiber including a plurality of core fibers.
 5. Thesystem of claim 4, wherein the damage affects a first subset of theplurality of core-fibers.
 6. The system of claim 5, wherein a secondsubset of the plurality of core fibers is unaffected by the damage suchthat multi-core optical fiber maintains at least partial functionalitybased on the second subset of the plurality of core-fibers.
 7. Thesystem of claim 6, wherein the at least partial functionality includesone or more of fluctuation sensing of a distal tip of the medicaldevice, shape sensing of the multi-core optical fiber, oximetrymonitoring, distal tip confirmation, distal tip location detection,detection of entry of the distal tip of the medical device into anAzygos vein, impedance or conductance sensing, intravascular ECGmonitoring or vessel cannulation detection.
 8. The system of claim 7,wherein the logic, when executed by the one or more processors, causesfurther operations including performing at least partial functionalityof the multi-core optical fiber without considering information providedby a first core fiber that has reflected a light signal having a firstunexpected spectral width.
 9. The system of claim 6, wherein the secondsubset of the plurality of core fibers includes redundant core fiberssuch that a shape sensing functionality of the multi-core optical fiberis maintained.
 10. The system of claim 1, wherein the medical device isone of an introducer wire, a guidewire, a stylet, a stylet within aneedle, a needle with the optical fiber inlayed into a cannula of theneedle or a catheter with the optical fiber inlayed into one or morewalls of the catheter.
 11. The system of claim 1, wherein the logic,when executed by the one or more processors, causes further operationsincluding: determining a first core fiber affected by the damage; anddetermining a location of the damage along the first core fiber.
 12. Thesystem of claim 11, wherein determining the first core fiber is based ona unique identifier assigned to the first core fiber and association ofunique identifier with each light signal reflected by the first corefiber.
 13. The system of claim 11, wherein determining the location ofthe damage includes identifying (i) a most distal sensor of the firstcore fiber from which a first light signal having an expected spectralwidth was received, and (ii) a most proximal sensor from which a secondlight signal having a first unexpected spectral width was received,second light signal having a reduction in intensity was received or acorresponding expected spectral width was not received.
 14. The systemof claim 1, wherein each of the plurality of sensors is a reflectivegrating, where each reflective grating alters its reflected light signalby applying a wavelength shift dependent on a strain experienced by thereflective grating.
 15. The system of claim 1, wherein the logic, whenexecuted by the one or more processors, causes further operationsincluding generating an alert indicating that the optical fiber has beendamaged.
 16. The system of claim 1, wherein the alert includes anindication of a location of damage. 17-48. (canceled)
 49. A medicaldevice system for detecting potential damage to an optical fibertechnology of a medical device, the system comprising: the medicaldevice comprising an optical fiber having one or more of core fibers,each of the one or more core fibers including a plurality of sensorsdistributed along a longitudinal length of a corresponding core fiberand each sensor of the plurality of sensors being configured to (i)reflect a light signal of a different spectral width based on receivedincident light, and (ii) change a characteristic of the reflected lightsignal for use in determining a physical state of the optical fiber; anda console including one or more processors and a non-transitorycomputer-readable medium having stored thereon logic, when executed bythe one or more processors, causes operations including: providing abroadband incident light signal to the optical fiber; receivingreflected light signals of different spectral widths of the broadbandincident light by one or more of the plurality of sensors; processingthe reflected light signals associated with the one or more core fibersto determine whether a first core fiber of the one or more core fibersis (i) positioned in a shape known to have a high likelihood of damagingthe first core fiber, or (ii) is experiencing strain known to have ahigh likelihood of damaging the first core fiber.